Sunday, August 2, 2009

Ever wondered why we laugh? Not why just as in, what are the things that make us laugh, but why as in, why did laughter ever came into being? This urge to laugh when someone falls off a chair seems to separate us from other animals and doesn't seem to serve any purpose at all. This is rather odd in a world of living things that evolved and optimized over billions of years, where everything in them has a purpose. Well, not everything, an appendix was never very useful to me other than in letting me know the inside of an operation's room, but is laughter just like the appendix? Just some weird spin-off of biological evolution? But even if it was, that would mean that it had a purpose once. So if we have it now, it's because for some reason, natural selection favored primitive men that laughed, so what is that reason?

We should start by attempting to describe what is this thing that we're talking about. What is laughter? We could describe it as the contraction of certain muscles in the face and as the vocalization in a set of patterns that are easily recognized as laughter. Now, although there's something truly unique related with laughter, laughter by itself doesn't seem to be anything that special and unique at all. The mechanism is imprinted in our genes and it can be seen in other animals too so the physiological mechanisms for the human's laugh isn't new; we also share many of the causes that trigger such a reaction, like joy, excitement and some forms of physical contact like tickling.

This is demonstrated by studies with other great apes and even in rats - yes, apparently some "science" was done that involved tickling rats. Now you might say that their laughter is very different than our own which still makes our "haha" special. Indeed our recognition of laughter in other species doesn't happen but isn't that what you would expect when there's no evolutionary pressure for us to do so? Regardless of any slight differences on the pattern of vocalizations and the exact muscles that are used, the underlying mechanism itself seems to be the same which makes laughter much more common and banal than we'd think.

So what's it's purpose? Laughter seems to be only one in a number of means of communication typically present in animals of a very social nature. Just like the movement of a dog's tail as a reaction to inner states of mind can be seen as an evolutionary advantage by improving communication between dogs. For an animal without a formal language like the one that developed on our civilization, the presence of a priori means of communication is absolutely necessary for any social creature to be social.

Laughter seems to fit this framework nicely but still, we can't help but think that there must be something genuinely unique in laughter. This is because we tend to associate laughter with humor and it's at humor that the line is drawn. Laughter, in this context, seems to have the role of broadcasting the recognition of humor.